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Find video protocols related to scientific articles indexed in Pubmed.
Mitochondrial DNA from El Mirador cave (Atapuerca, Spain) reveals the heterogeneity of Chalcolithic populations.
PLoS ONE
PUBLISHED: 08-12-2014
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Previous mitochondrial DNA analyses on ancient European remains have suggested that the current distribution of haplogroup H was modeled by the expansion of the Bell Beaker culture (ca 4,500-4,050 years BP) out of Iberia during the Chalcolithic period. However, little is known on the genetic composition of contemporaneous Iberian populations that do not carry the archaeological tool kit defining this culture. Here we have retrieved mitochondrial DNA (mtDNA) sequences from 19 individuals from a Chalcolithic sample from El Mirador cave in Spain, dated to 4,760-4,200 years BP and we have analyzed the haplogroup composition in the context of modern and ancient populations. Regarding extant African, Asian and European populations, El Mirador shows affinities with Near Eastern groups. In different analyses with other ancient samples, El Mirador clusters with Middle and Late Neolithic populations from Germany, belonging to the Rössen, the Salzmünde and the Baalberge archaeological cultures but not with contemporaneous Bell Beakers. Our analyses support the existence of a common genetic signal between Western and Central Europe during the Middle and Late Neolithic and points to a heterogeneous genetic landscape among Chalcolithic groups.
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Leptin deficiency in vivo enhances the ability of splenic dendritic cells to activate T cells.
Int. Immunol.
PUBLISHED: 06-25-2014
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Leptin is a pleiotropic adipokine that is critical for regulating food intake and energy expenditure and also participates in functions of the immune system, including those of antigen-presenting cells. Here, we assess the effect of leptin deficiency on the function splenic dendritic cells (sDC). sDC from leptin-deficient mice (Lep(ob)) were evaluated ex vivo for phenotype, ability to respond to inflammatory stimuli, to acquire and process antigens and to activate T cells. The data show that Lep(ob) sDC express activation markers similar to controls and respond similarly to LPS activation or anti-CD40 cross-linking. In addition, antigen acquisition and processing by Lep(ob) sDC was similar to controls. However, Lep(ob) sDC elicited higher production of IFN-? in mixed lymphocyte reactions and increased production of IL-2 by antigen-specific T-cell hybridoma relative to controls. To assess Lep(ob) sDC activation of T cells in vivo, Lep(ob) and control mice were infected systemically with Mycobacterium avium. Lep(ob) mice were significantly better at neutralizing the infection as measured by splenic bacterial load over time. This was mirrored with an increased percentage of activated T cells in M. avium-infected Lep(ob) mice. Thus, although no changes were detected in sDC phenotype, activation, antigen processing or presentation, these DC surprisingly presented an enhanced ability to activate T cells ex vivo and in vivo. These data demonstrate that leptin can modulate DC function and suggest that leptin may dampen T-cell responsiveness in the physiological setting.
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Analysis of structural diversity in wolf-like canids reveals post-domestication variants.
BMC Genomics
PUBLISHED: 05-14-2014
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Although a variety of genetic changes have been implicated in causing phenotypic differences among dogs, the role of copy number variants (CNVs) and their impact on phenotypic variation is still poorly understood. Further, very limited knowledge exists on structural variation in the gray wolf, the ancestor of the dog, or other closely related wild canids. Documenting CNVs variation in wild canids is essential to identify ancestral states and variation that may have appeared after domestication.
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Genomic analysis of the blood attributed to Louis XVI (1754-1793), king of France.
Sci Rep
PUBLISHED: 03-27-2014
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A pyrographically decorated gourd, dated to the French Revolution period, has been alleged to contain a handkerchief dipped into the blood of the French king Louis XVI (1754-1793) after his beheading but recent analyses of living males from two Bourbon branches cast doubts on its authenticity. We sequenced the complete genome of the DNA contained in the gourd at low coverage (~2.5×) with coding sequences enriched at a higher ~7.3× coverage. We found that the ancestry of the gourd's genome does not seem compatible with Louis XVI's known ancestry. From a functional perspective, we did not find an excess of alleles contributing to height despite being described as the tallest person in Court. In addition, the eye colour prediction supported brown eyes, while Louis XVI had blue eyes. This is the first draft genome generated from a person who lived in a recent historical period; however, our results suggest that this sample may not correspond to the alleged king.
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Pesticide exposure on sloths (Bradypus variegatus and Choloepus hoffmanni) in an agricultural landscape of Northeastern Costa Rica.
J Environ Biol
PUBLISHED: 03-04-2014
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Between 2005 and 2008, wild Bradypus variegatus and Choloepus hoffmanni inhabiting an agricultural landscape and captive animals from a rescue center in Northeastern Costa Rica were studied to assess exposure to pesticides. A total of 54 animals were sampled: 42 wild sloths captured at an agricultural landscape and 12 captive animals from a rescue center. Pesticides' active ingredients were determined in three sample matrices: hair, aqueous mixture (paws' wash) and cotton gauze (mouth clean) based on multi-residue gas chromatography methods. Recoveries tests ranged from 73 to 146% and relative standard deviations were less than 20% throughout all the recovery tests. Active ingredients detected in sloths samples were ametryn, chlorothalonil, chlorpyrifos, diazinon, difenoconazole, ethoprophos and thiabendazole. These active ingredients were used in intensive agricultural production for bananas, pineapples and other crops. Blood plasma cholinesterase activity (PChE) was determined by the Ellman method modified for micro plates. Enzyme activity determination was normalized to protein content in the samples according to Bradford method. Wild sloth PChE activity was similar for both species while sloths in captivity showed differences between species. Enzyme activity was significantly lower for two-toed sloths. This study showed that sloths were exposed to pesticides that caused acute and chronic effect in mammals and can also be a threat to other wildlife species. There is a need to better understand the potential effects of exposure to pesticides in sloths and other wild mammal populations, especially those threatened or endangered. More studies in this field must be carried out on the wildlife fauna inhabiting the agricultural landscape and its surroundings.
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Derived immune and ancestral pigmentation alleles in a 7,000-year-old Mesolithic European.
Nature
PUBLISHED: 01-26-2014
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Ancient genomic sequences have started to reveal the origin and the demographic impact of farmers from the Neolithic period spreading into Europe. The adoption of farming, stock breeding and sedentary societies during the Neolithic may have resulted in adaptive changes in genes associated with immunity and diet. However, the limited data available from earlier hunter-gatherers preclude an understanding of the selective processes associated with this crucial transition to agriculture in recent human evolution. Here we sequence an approximately 7,000-year-old Mesolithic skeleton discovered at the La Braña-Arintero site in León, Spain, to retrieve a complete pre-agricultural European human genome. Analysis of this genome in the context of other ancient samples suggests the existence of a common ancient genomic signature across western and central Eurasia from the Upper Paleolithic to the Mesolithic. The La Braña individual carries ancestral alleles in several skin pigmentation genes, suggesting that the light skin of modern Europeans was not yet ubiquitous in Mesolithic times. Moreover, we provide evidence that a significant number of derived, putatively adaptive variants associated with pathogen resistance in modern Europeans were already present in this hunter-gatherer.
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A small library of synthetic di-substituted 1, 4-naphthoquinones induces ROS-mediated cell death in murine fibroblasts.
PLoS ONE
PUBLISHED: 01-01-2014
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Synthesis of compound libraries and their concurrent assessment as selective reagents for probing and modulating biological function continues to be an active area of chemical biology. Microwave-assisted solid-phase Dötz benzannulation reactions have been used to inexpensively synthesize 2, 3-disubstituted-1, 4-naphthoquinone derivatives. Herein, we report the biological testing of a small library of such compounds using a murine fibroblast cell line (L929). Assessment of cellular viability identified three categories of cytotoxic compounds: no toxicity, low/intermediate toxicity and high toxicity. Increased levels of Annexin-V-positive staining and of caspase 3 activity confirmed that low, intermediate, and highly toxic compounds promote cell death. The compounds varied in their ability to induce mitochondrial depolarization and formation of reactive oxygen species (ROS). Both cytotoxic and non-cytotoxic compounds triggered mitochondrial depolarization, while one highly cytotoxic compound did not. In addition, all cytotoxic compounds promoted increased intracellular ROS but the cells were only partially protected from compound-induced apoptosis when in the presence of superoxide dismutase, catalase, or ascorbic acid suggesting utilization of additional pro-death mechanisms. In summary, nine of twelve (75%) 1, 4-naphthoquinone synthetic compounds were cytotoxic. Although the mitochondria did not appear to be a central target for induction of cell death, all of the cytotoxic compounds induced ROS formation. Thus, the data demonstrate that the synthesis regime effectively created cytotoxic compounds highlighting the potential use of the regime and its products for the identification of biologically relevant reagents.
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Genome sequencing highlights the dynamic early history of dogs.
PLoS Genet.
PUBLISHED: 01-01-2014
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To identify genetic changes underlying dog domestication and reconstruct their early evolutionary history, we generated high-quality genome sequences from three gray wolves, one from each of the three putative centers of dog domestication, two basal dog lineages (Basenji and Dingo) and a golden jackal as an outgroup. Analysis of these sequences supports a demographic model in which dogs and wolves diverged through a dynamic process involving population bottlenecks in both lineages and post-divergence gene flow. In dogs, the domestication bottleneck involved at least a 16-fold reduction in population size, a much more severe bottleneck than estimated previously. A sharp bottleneck in wolves occurred soon after their divergence from dogs, implying that the pool of diversity from which dogs arose was substantially larger than represented by modern wolf populations. We narrow the plausible range for the date of initial dog domestication to an interval spanning 11-16 thousand years ago, predating the rise of agriculture. In light of this finding, we expand upon previous work regarding the increase in copy number of the amylase gene (AMY2B) in dogs, which is believed to have aided digestion of starch in agricultural refuse. We find standing variation for amylase copy number variation in wolves and little or no copy number increase in the Dingo and Husky lineages. In conjunction with the estimated timing of dog origins, these results provide additional support to archaeological finds, suggesting the earliest dogs arose alongside hunter-gathers rather than agriculturists. Regarding the geographic origin of dogs, we find that, surprisingly, none of the extant wolf lineages from putative domestication centers is more closely related to dogs, and, instead, the sampled wolves form a sister monophyletic clade. This result, in combination with dog-wolf admixture during the process of domestication, suggests that a re-evaluation of past hypotheses regarding dog origins is necessary.
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Influence of human immune cells on cancer: studies at the University of Colorado.
Immunol. Res.
PUBLISHED: 06-14-2013
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There will be over half a million cancer-related deaths in the United States in 2012, with lung cancer being the leader followed by prostate in men and breast in women. There is estimated to be more than one and a half million new cases of cancer in 2012, making the development of effective therapies a high priority. As tumor immunologists, we are interested in the development of immunotherapies because the immune response offers exquisite specificity and the potential to target tumor cells without harming normal cells. In this review, we highlight the current advances in the field of immunotherapy and the current work being completed by laboratories at University of Colorado School of Medicine in multiple malignancies, including breast cancer, lung cancer, melanoma, thyroid cancer, and glioblastoma. This work focuses on augmenting the anti-tumor response of CD8 T cells in the blood, lymph nodes, and tumors of patients, determining biomarkers for patients who are more likely to respond to immunotherapy, and identifying additional anti-tumor and immunosuppressive cells that influence the overall response to tumors. These collaborative efforts will identify mechanisms to improve immune function, which may elucidate therapeutic targets for clinical trials to improve patient health and survival.
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Myeloid-derived suppressor cells are associated with disease progression and decreased overall survival in advanced-stage melanoma patients.
Cancer Immunol. Immunother.
PUBLISHED: 06-11-2013
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Myeloid-derived suppressor cells are increased in the peripheral blood of advanced-stage cancer patients; however, no studies have shown a correlation of these immunosuppressive cells with clinical outcomes in melanoma patients. We characterized the frequency and suppressive function of multiple subsets of myeloid-derived suppressor cells in the peripheral blood of 34 patients with Stage IV melanoma, 20 patients with Stage I melanoma, and 15 healthy donors. The frequency of CD14+ MDSCs (Lin- CD11b+ HLA-DR- CD14+ CD33+) and CD14- MDSCs (Lin- CD11b+ HLA-DR- CD14- CD33+) was increased in the peripheral blood of Stage IV melanoma patients relative to healthy donors. The frequency of CD14+ and CD14- MDSCs correlated with each other and with the increased frequency of regulatory T cells, but not with classically defined monocytes. CD14- MDSCs isolated from the peripheral blood of Stage IV melanoma patients suppressed T cell activation more than those isolated from healthy donors, and the frequency of these cells correlated with disease progression and decreased overall survival. Our study provides the first evidence that the frequency of CD14- MDSCs negatively correlates with clinical outcomes in advanced-stage melanoma patients. These data indicate that suppressive MDSCs should be considered as targets for future immunotherapies.
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Population connectivity buffers genetic diversity loss in a seabird.
Front. Zool.
PUBLISHED: 03-04-2013
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Ancient DNA has revolutionized conservation genetic studies as it allows monitoring of the genetic variability of species through time and predicting the impact of ecosystems threats on future population dynamics and viability. Meanwhile, the consequences of anthropogenic activities and climate change to island faunas, particularly seabirds, remain largely unknown. In this study, we examined temporal changes in the genetic diversity of a threatened seabird, the Corys shearwater (Calonectris borealis).
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Accelerated exon evolution within primate segmental duplications.
Genome Biol.
PUBLISHED: 01-29-2013
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BACKGROUND: The identification of signatures of natural selection has long been used as an approach to understanding the unique features of any given species. Genes within segmental duplications are overlooked in most studies of selection due to the limitations of draft nonhuman genome assemblies and to the methodological reliance on accurate gene trees, which are difficult to obtain for duplicated genes. RESULTS: In this work, we detected exons with an accumulation of high-quality nucleotide differences between the human assembly and shotgun sequencing reads from single human and macaque individuals. Comparing the observed rates of nucleotide differences between coding exons and their flanking intronic sequences with a likelihood-ratio test, we identified 74 exons with evidence for rapid coding sequence evolution during the evolution of humans and Old World monkeys. Fifty-five percent of rapidly evolving exons were either partially or totally duplicated, which is a significant enrichment of the 6% rate observed across all human coding exons. CONCLUSIONS: Our results provide a more comprehensive view of the action of selection upon segmental duplications, which are the most complex regions of our genomes. In light of these findings, we suggest that segmental duplications could be subjected to rapid evolution more frequently than previously thought.
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The genome sequencing of an albino Western lowland gorilla reveals inbreeding in the wild.
BMC Genomics
PUBLISHED: 01-14-2013
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The only known albino gorilla, named Snowflake, was a male wild born individual from Equatorial Guinea who lived at the Barcelona Zoo for almost 40 years. He was diagnosed with non-syndromic oculocutaneous albinism, i.e. white hair, light eyes, pink skin, photophobia and reduced visual acuity. Despite previous efforts to explain the genetic cause, this is still unknown. Here, we study the genetic cause of his albinism and making use of whole genome sequencing data we find a higher inbreeding coefficient compared to other gorillas.
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A high throughput genotyping approach reveals distinctive autosomal genetic signatures for European and Near Eastern wild boar.
PLoS ONE
PUBLISHED: 01-07-2013
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The lack of a Near Eastern genetic signature in modern European porcine breeds indicates that, although domestic pigs from the Fertile Crescent entered Europe during the Neolithic, they were completely replaced by their European counterparts in a short window of time. Whilst the absence of such genetic signature has been convincingly demonstrated at the mitochondrial level, variation at the autosomal genomes of European and Near Eastern Sus scrofa has not been compared yet. Herewith, we have explored the genetic relationships among 43 wild boar from Europe (N?=?21), Near East (N?=?19) and Korea (N?=?3), and 40 Iberian (N?=?16), Canarian (N?=?4) and Mangalitza (N?=?20) pigs by using a high throughput SNP genotyping platform. After data filtering, 37,167 autosomal SNPs were used to perform population genetics analyses. A multidimensional scaling plot based on genome-wide identity-by-state pairwise distances inferred with PLINK showed that Near Eastern and European wild boar populations are genetically differentiated. Maximum likelihood trees built with TreeMix supported this conclusion i.e. an early population split between Near Eastern and European Sus scrofa was observed. Moreover, analysis of the data with Structure evidenced that the sampled Iberian, Canarian and Mangalitza pigs did not carry any autosomal signature compatible with a Near Eastern ancestry, a finding that agrees well with previous mitochondrial studies.
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Temporal and spatial resource use by female three-toed sloths and their young in an agricultural landscape in Costa Rica.
Rev. Biol. Trop.
PUBLISHED: 12-30-2011
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The information on ecological behavior of wild sloths is very scarce. In this study we determined the home ranges and resources used by three adult female three-toed sloths (Bradypus variegatus) and their four young in an agricultural matrix of cacao (Theobroma cacao), pasture, riparian forests and living fencerows in Costa Rica. Births occurred during November-December and the young became independent at five to seven months of age. Initially, mothers remained fixed in one or a few trees, but expanded their use of resources as young sloths became independent from them. Mothers initially guided the young to preferred food and cover resources, but they gradually left their young in small nucleus areas and colonized new areas for themselves. Home range sizes for young sloths (up to seven months of age) varied between 0.04-0.6 hectares, while home range sizes for mothers varied from 0.04-25.0 hectares. During the maternal care period, 22 tree species were used, with the most common being Cecropia obtusifolia (30.9%), Coussapoa villosa (25.6%), Nectandra salicifolia (12.1%), Pterocarpus officinalis (5.8%) and Samanea saman (5.4%). However, young sloths used only 20 tree species, with the most common being C. villosa (18.4%), S. saman (18.5%) and N. salicifolia (16.7%). The cacao agroforest was used only by mother sloths and never by their young following separation. However, in the riparian forest, both mother sloths and young used the tree species. A total of 28 tree species were used by the mother sloth; including the food species: C. obtusifolia, C. villosa, N. salicifolia and P. officinalis. However, the young used 18 trees species in this habitat with N. salicifolia and S. saman most commonly used, although they rested and fed during the day in C. obtusifolia, C. villosa and O. sinnuata. The cacao agroforest with adjacent riparian forests and fencerows provides an important habitat type that links the smaller secondary forests and other patches.
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Tuberculosis of the spine. A systematic review of case series.
Int Orthop
PUBLISHED: 10-30-2011
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The objective of this systematic review was to characterise the methodological issues, as well as clinical, diagnosis, microbiological and treatment characteristics of patients with spinal tuberculosis.
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[Septic shock by Vibrio vulnificus at the coast Gulf of Mexico].
Rev Med Inst Mex Seguro Soc
PUBLISHED: 10-11-2011
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Vibrio vulnificus is a Gram-negative bacterium which is found in marine environments and where there is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea. The infection by these bacteria can cause primary septicemia by two mechanisms: upon consuming crustaceans, mollusks and some fish (filtering shellfish) raw or barely cooked or by an open injury in contact with seawater. The patients with infections of the primary injury by Vibrio vulnificus developed contaminated painful cellulitis that progresses quickly as well as a marked local inflammation with signs of hemorrhaging. We described a case of Vibrio vulnificus sepsis, with emphasis on the clinical picture, the epidemiological background and lab findings; finally we did a brief review of the literature related to the case.
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50,000 years of genetic uniformity in the critically endangered Iberian lynx.
Mol. Ecol.
PUBLISHED: 08-22-2011
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Low genetic diversity in the endangered Iberian lynx, including lack of mitochondrial control region variation, is thought to result from historical or Pleistocene/Holocene population bottlenecks, and to indicate poor long-term viability. We find no variability in control region sequences from 19 Iberian lynx remains from across the Iberian Peninsula and spanning the last 50,000 years. This is best explained by continuously small female effective population size through time. We conclude that low genetic variability in the Iberian lynx is not in itself a threat to long-term viability, and so should not preclude conservation efforts.
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Fragmentation of contaminant and endogenous DNA in ancient samples determined by shotgun sequencing; prospects for human palaeogenomics.
PLoS ONE
PUBLISHED: 06-30-2011
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Despite the successful retrieval of genomes from past remains, the prospects for human palaeogenomics remain unclear because of the difficulty of distinguishing contaminant from endogenous DNA sequences. Previous sequence data generated on high-throughput sequencing platforms indicate that fragmentation of ancient DNA sequences is a characteristic trait primarily arising due to depurination processes that create abasic sites leading to DNA breaks. METHODOLOGY/PRINCIPALS FINDINGS: To investigate whether this pattern is present in ancient remains from a temperate environment, we have 454-FLX pyrosequenced different samples dated between 5,500 and 49,000 years ago: a bone from an extinct goat (Myotragus balearicus) that was treated with a depurinating agent (bleach), an Iberian lynx bone not subjected to any treatment, a human Neolithic sample from Barcelona (Spain), and a Neandertal sample from the El Sidrón site (Asturias, Spain). The efficiency of retrieval of endogenous sequences is below 1% in all cases. We have used the non-human samples to identify human sequences (0.35 and 1.4%, respectively), that we positively know are contaminants.
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Hematology and clinical chemistry values of free-ranging basilisk lizards (Basiliscus plumifrons) in Costa Rica.
J. Zoo Wildl. Med.
PUBLISHED: 06-01-2011
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Twenty-three lizards were captured for this study, both males and females (12 males, 10 females, 1 undetermined), with a large range in body weights (40-286 g) appeared to be healthy based on activity level, physical examinations, and body condition scores. Heparinized blood samples from 20 free-ranging basilisk lizards (Basiliscus plumifrons) in Costa Rica were used for determining complete blood cell counts, plasma, and heparinized whole blood biochemical analysis. This information will serve as baseline reference data for future health assessment studies of free-ranging and captive basilisk lizards, as well as epidemiologic, conservation, and captive-breeding studies. A point-of-care analyzer was useful for this field study, and clinical chemistry values from heparinized whole blood samples were similar to values from plasma, which indicates that separation of plasma may not be necessary to process blood samples on site in remote areas. To the authors knowledge, this is the first report of hematologic and plasma biochemical data from free-ranging B. plumnifrons.
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Phase I safety and immunogenicity trial of Plasmodium vivax CS derived long synthetic peptides adjuvanted with montanide ISA 720 or montanide ISA 51.
Am. J. Trop. Med. Hyg.
PUBLISHED: 02-05-2011
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We assessed the safety, tolerability, and immunogenicity of a mixture of three synthetic peptides derived from the Plasmodium vivax circumsporozoite protein formulated in Montanide ISA 720 or Montanide ISA 51. Forty healthy malaria-naive volunteers were allocated to five experimental groups (A-E): four groups (A-D) were immunized intramuscularly with 50 and 100 ?g/dose injections of a mixture of N, R, and C peptides formulated in the two different adjuvants at 0, 2, and 4 months and one group was administered placebo. Vaccines were immunogenic, safe, well tolerated, and no serious adverse events related to the vaccine occurred. Seroconversion occurred in > 90% of the vaccines and antibodies recognized the sporozoite protein on immunofluorescent antibody test. Vaccines in Montanide ISA 51 showed a higher sporozoite protein recognition and interferon production. Results encourage further testing of the vaccine protective efficacy.
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Consistent safety and infectivity in sporozoite challenge model of Plasmodium vivax in malaria-naive human volunteers.
Am. J. Trop. Med. Hyg.
PUBLISHED: 02-05-2011
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A safe and reproducible Plasmodium vivax infectious challenge method is required to evaluate the efficacy of malaria vaccine candidates. Seventeen healthy Duffy (+) and five Duffy (-) subjects were randomly allocated into three (A-C) groups and were exposed to the bites of 2-4 Anopheles albimanus mosquitoes infected with Plasmodium vivax derived from three donors. Duffy (-) subjects were included as controls for each group. Clinical manifestations of malaria and parasitemia were monitored beginning 7 days post-challenge. All Duffy (+) volunteers developed patent malaria infection within 16 days after challenge. Prepatent period determined by thick smear, was longer for Group A (median 14.5 d) than for Groups B and C (median 10 d/each). Infected volunteers recovered rapidly after treatment with no serious adverse events. The bite of as low as two P. vivax-infected mosquitoes provides safe and reliable infections in malaria-naive volunteers, suitable for assessing antimalarial and vaccine efficacy trials.
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Genetic evidence for patrilocal mating behavior among Neandertal groups.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 12-20-2010
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The remains of 12 Neandertal individuals have been found at the El Sidrón site (Asturias, Spain), consisting of six adults, three adolescents, two juveniles, and one infant. Archaeological, paleontological, and geological evidence indicates that these individuals represent all or part of a contemporaneous social group of Neandertals, who died at around the same time and later were buried together as a result of a collapse of an underground karst. We sequenced phylogenetically informative positions of mtDNA hypervariable regions 1 and 2 from each of the remains. Our results show that the 12 individuals stem from three different maternal lineages, accounting for seven, four, and one individual(s), respectively. Using a Y-chromosome assay to confirm the morphological determination of sex for each individual, we found that, although the three adult males carried the same mtDNA lineage, each of the three adult females carried different mtDNA lineages. These findings provide evidence to indicate that Neandertal groups not only were small and characterized by low genetic diversity but also were likely to have practiced patrilocal mating behavior.
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Outcomes after related and unrelated umbilical cord blood transplantation for hereditary bone marrow failure syndromes other than Fanconi anemia.
Haematologica
PUBLISHED: 11-11-2010
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Allogeneic stem cell transplantation is the only curative option for patients with hereditary bone marrow failure syndromes. Umbilical cord blood is an alternative source of stem cells for allogeneic transplantation.
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Inhibition of neuronal nitric oxide synthase prevents alterations in medial prefrontal cortex excitability induced by repeated cocaine administration.
Psychopharmacology (Berl.)
PUBLISHED: 08-17-2010
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The medial prefrontal cortex (mPFC), a forebrain region that regulates cognitive function and reward-motivated behaviors, has been implicated in the neuropathological mechanisms of drug addiction and withdrawal. In cocaine-abstinent human addicts, neuronal activity of the mPFC is increased in response to cocaine re-exposure or drug-associated cues. Additionally, repeated cocaine exposure alters the membrane properties and ion channel function of mPFC pyramidal neurons in drug-withdrawn rats, leading to an increased firing in response to excitatory stimuli. Nitric oxide (NO), a diffusible neuromodulator of neuronal excitability, may play a role in initiating and maintaining behavioral effects of psychostimulants. However, the role of NO in the mechanisms by which cocaine affects membrane excitability is not well clarified.
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The intra-hippocampal leucine administration impairs memory consolidation and LTP generation in rats.
Cell. Mol. Neurobiol.
PUBLISHED: 06-08-2010
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Leucine accumulates in fluids and tissues of patients affected by maple syrup urine disease, an inherited metabolic disorder, predominantly characterized by neurological dysfunction. Although, a variable degree of cognition/psychomotor delay/mental retardation is found in a considerable number of individuals affected by this deficiency, the mechanisms underlying the neuropathology of these alterations are still not defined. Therefore, the aim of this study was to investigate the effect of acute intra-hippocampal leucine administration in the step-down test in rats. In addition, the leucine effects on the electrophysiological parameter, long-term potentiation generation, and on the activities of the respiratory chain were also investigated. Male Wistar rats were bilaterally administrated with leucine (80 nmol/hippocampus; 160 nmol/rat) or artificial cerebrospinal fluid (controls) into the hippocampus immediately post-training in the behavioral task. Twenty-four hours after training in the step-down test, the latency time was evaluated and afterwards animals were sacrificed for assessing the ex vivo biochemical measurements. Leucine-treated animals showed impairment in memory consolidation and a complete inhibition of long-term potentiation generation at supramaximal stimulation. In addition, a significant increment in complex IV activity was observed in hippocampus from leucine-administered rats. These data strongly indicate that leucine compromise memory consolidation, and that impairment of long-term potentiation generation and unbalance of the respiratory chain may be plausible mechanisms underlying the deleterious leucine effect on cognition.
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Ghrelin induced memory facilitation implicates nitric oxide synthase activation and decrease in the threshold to promote LTP in hippocampal dentate gyrus.
Physiol. Behav.
PUBLISHED: 04-01-2010
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Although the hypothalamus has been long considered the main ghrelin (Ghr) target organ mediating orexigenic effects, recently it has been shown that in-vivo Ghr hippocampus administration improves learning and memory in the inhibitory avoidance paradigm. However, the possible mechanisms underlying this memory facilitation effect have not been clarified. Given that the biochemical memory cascade into the hippocampus involves nitric oxide (NO) synthesis via NO synthase (NOS) activation, we investigated 1) if Ghr administration modulated NOS activity in the hippocampus; and 2) if hippocampal NOS inhibition influenced Ghr-induced memory facilitation, using a behavioral paradigm, biochemical determinations and an electrophysiological model. Our results showed that intra-hippocampal Ghr administration increased the NOS activity in a dose dependent manner, and reduced the threshold for LTP generation in dentate gyrus of rat hippocampus. Moreover, pre-administration of NG-nitro-l-arginine (l-NOArg) in the hippocampus partially prevented the Ghr-induced memory improvement, abolished the increase in NOS activity, and prevented the decreased threshold to generate LTP induced by Ghr. These findings suggest that activation of the NOS/NO pathway in hippocampus participates in the effects of Ghr on memory consolidation and is related with plastic properties of the hippocampal three-synaptic loop.
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Rotavirus infection activates dendritic cells from Peyers patches in adult mice.
J. Virol.
PUBLISHED: 12-09-2009
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This study used an in vivo mouse model to analyze the response of dendritic cells (DCs) in Peyers patches (PPs) within the first 48 h of infection with the wild-type murine rotavirus EDIM (EDIM(wt)). After the infection, the absolute number of DCs was increased by 2-fold in the PPs without a modification of their relative percentage of the total cell number. Also, the DCs from PPs of infected mice showed a time-dependent migration to the subepithelial dome (SED) and an increase of the surface activation markers CD40, CD80, and CD86. This response was more evident at 48 h postinfection (p.i.) and depended on viral replication, since DCs from PPs of mice inoculated with UV-treated virus did not show this phenotype. As a result of the activation, the DCs showed an increase in the expression of mRNA for the proinflammatory cytokines interleukin-12/23p40 (IL-12/23p40), tumor necrosis factor alpha (TNF-alpha), and beta interferon (IFN-beta), as well as for the regulatory cytokine IL-10. These results suggest that, a short time after rotavirus infection, the DCs from PPs play a critical role in controlling the infection and, at the same time, avoiding an excessive inflammatory immune response.
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A bi-dimensional genome scan for prolificacy traits in pigs shows the existence of multiple epistatic QTL.
BMC Genomics
PUBLISHED: 06-15-2009
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Prolificacy is the most important trait influencing the reproductive efficiency of pig production systems. The low heritability and sex-limited expression of prolificacy have hindered to some extent the improvement of this trait through artificial selection. Moreover, the relative contributions of additive, dominant and epistatic QTL to the genetic variance of pig prolificacy remain to be defined. In this work, we have undertaken this issue by performing one-dimensional and bi-dimensional genome scans for number of piglets born alive (NBA) and total number of piglets born (TNB) in a three generation Iberian by Meishan F(2) intercross.
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Identical twin face lifts with differing techniques: a 10-year follow-up.
Plast. Reconstr. Surg.
PUBLISHED: 03-26-2009
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To evaluate the efficacies of four different surgical techniques in facial rejuvenation, two sets of identical twins were operated on by four different surgeons. The technical approaches to facial rejuvenation included lateral superficial musculoaponeurotic system (SMAS)-ectomy with extensive skin undermining, composite rhytidectomy, SMAS-platysma flap with bidirectional lift, and endoscopic midface lift with an open anterior platysmaplasty. All patients were photographed by an independent surgeon at 1, 6, and 10 years postoperatively. At the same time interval, the cases were presented and discussed in a panel format at the annual meeting of the American Society for Aesthetic Plastic Surgery. Each operating surgeon was allowed to critique the results and discuss how his methods had changed over the intervening 10-year interval. Postoperative photographs at 1, 6, and 10 years after surgery are included to allow the reader to examine long-term results utilizing various approaches to facial rejuvenation in identical twins.
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Paleogenomics in a temperate environment: shotgun sequencing from an extinct Mediterranean caprine.
PLoS ONE
PUBLISHED: 03-05-2009
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Numerous endemic mammals, including dwarf elephants, goats, hippos and deers, evolved in isolation in the Mediterranean islands during the Pliocene and Pleistocene. Most of them subsequently became extinct during the Holocene. Recently developed high-throughput sequencing technologies could provide a unique tool for retrieving genomic data from these extinct species, making it possible to study their evolutionary history and the genetic bases underlying their particular, sometimes unique, adaptations. METHODOLOGY/PRINCIPALS FINDINGS: A DNA extraction of a approximately 6,000 year-old bone sample from an extinct caprine (Myotragus balearicus) from the Balearic Islands in the Western Mediterranean, has been subjected to shotgun sequencing with the GS FLX 454 platform. Only 0.27% of the resulting sequences, identified from alignments with the cow genome and comprising 15,832 nucleotides, with an average length of 60 nucleotides, proved to be endogenous.
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Sauroine, an alkaloid from Huperzia saururus with activity in wistar rats in electrophysiological and behavioral assays related to memory retention.
J. Nat. Prod.
PUBLISHED: 02-20-2009
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The present study describes the effects of sauroine (1), the main alkaloid obtained from Huperzia saururus, on memory retention and learning. To evaluate this, electrophysiological experiments and behavioral tests (step down) were performed on male Wistar rats. The results showed that 1 improved memory retention in the step-down test, significantly increasing hippocampal plasticity. Thus, 1 seems to be a constituent responsible for the activity claimed in folk medicine for H. saururus in Argentina.
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The Peruvian fishermans knot: a new, simple, and versatile self-locking sliding knot.
Ann Plast Surg
PUBLISHED: 01-23-2009
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In many plastic surgery operations that are undertaken through relatively small incisions resulting in deep-seated operating fields, sliding knots with a self-locking property are preferred by plastic surgeons for 3 reasons: simplicity, reliability, and versatility. We describe a new and versatile sliding knot that can be easily sledded and locked.
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Comparative hematologic analysis of uncomplicated malaria in uniquely different regions of unstable transmission in Brazil and Colombia.
Am. J. Trop. Med. Hyg.
PUBLISHED: 01-15-2009
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Information on malaria-associated anemia in adult patients is scarce in South American populations. From 2004 to 2006, malaria patients 18 to 45 years of age were recruited in a descriptive cross-sectional study from two different towns: Manaus, in the Brazilian Amazon (120 patients) where Plasmodium falciparum incidence is lower ( approximately 20%), and in Tumaco on the Colombian Pacific Coast (126 patients) where P. falciparum incidence is higher ( approximately 90%). Relationships between hematologic parameters and independent variables were explored using cross-tabulations and multiple linear regression analyses. We found an inverse relationship of hemoglobin (Hb) levels with days of illness in both sites. In Manaus but not in Tumaco, red cell distribution width (RDW) was related to asexual parasitemia. Reticulocytes were higher in Plasmodium vivax infection in Tumaco. Only in Tumaco, two patients with P. falciparum infection presented with severe anemia (Hb < 7 g/dL). Etiologic factors associated with hematologic changes in malaria seem to be multifactorial. More studies are needed to clarify the anemia determinants in uncomplicated malaria in South America, where malaria transmission is mostly unstable.
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Component separations.
Semin Plast Surg
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Component separation is a technique used to provide adequate coverage for midline abdominal wall defects such as a large ventral hernia. This surgical technique is based on subcutaneous lateral dissection, fasciotomy lateral to the rectus abdominis muscle, and dissection on the plane between external and internal oblique muscles with medial advancement of the block that includes the rectus muscle and its fascia. This release allows for medial advancement of the fascia and closure of up to 20-cm wide defects in the midline area. Since its original description, components separation technique underwent multiple modifications with the ultimate goal to decrease the morbidity associated with the traditional procedure. The extensive subcutaneous lateral dissection had been associated with ischemia of the midline skin edges, wound dehiscence, infection, and seroma. Although the current trend is to proceed with minimally invasive component separation and to reinforce the fascia with mesh, the basic principles of the techniques as described by Ramirez et al in 1990 have not changed over the years. Surgeons who deal with the management of abdominal wall defects are highly encouraged to include this technique in their collection of treatment options.
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Genetic comparison of the head of Henri IV and the presumptive blood from Louis XVI (both Kings of France).
Forensic Sci. Int.
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A mummified head was identified in 2010 as belonging to Henri IV, King of France. A putative blood sample from the King Louis XVI preserved into a pyrographically decorated gourd was analyzed in 2011. Both kings are in a direct male-line descent, separated by seven generations. We have retrieved the hypervariable region 1 of the mitochondrial DNA as well as a partial Y-chromosome profile from Henri IV. Five STR loci match the alleles found in Louis XVI, while another locus shows an allele that is just one mutation step apart. Taking into consideration that the partial Y-chromosome profile is extremely rare in modern human databases, we concluded that both males could be paternally related. The likelihood ratio of the two samples belonging to males separated by seven generations (as opposed to unrelated males) was estimated as 246.3, with a 95% confidence interval between 44.2 and 9729. Historically speaking, this forensic DNA data would confirm the identity of the previous Louis XVI sample, and give another positive argument for the authenticity of the head of Henri IV.
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The 1-2-3 approach to abdominal packing.
World J Surg
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Abdominal packing (AP) in damage-control laparotomy (DCL) is a lifesaving technique that controls coagulopathic hemorrhage in severely injured trauma patients. However, the impact of the duration of AP on the incidence of re-bleeding and on intra-abdominal infections in penetrating abdominal trauma is not clear. The objective of the present study was to evaluate the complications related to the duration of AP and to determine the optimal time for AP removal.
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Impact of contextual cues in the expression of the memory associated with diazepam withdrawal: involvement of hippocampal PKM? in vivo, and Arc expression and LTP in vitro.
Eur. J. Neurosci.
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Hippocampal synaptic plasticity has been related to learning and adaptive processes developed during chronic drug administration, suggesting the existence of a common neurobiological mechanism mediating drug addiction and memory. Moreover, protein kinase M zeta (PKM?) is critical for the maintenance of hippocampal long-term potentiation (LTP) and spatial conditioned long-term memories. Also, a link between activity-regulated cytoskeleton-associated protein (Arc), PKM? and LTP has been proposed. Our previous results demonstrated that re-exposure to the withdrawal environment was able to evoke the memory acquired when the anxiety measured as a diazepam (DZ) withdrawal sign was experienced. In the present work we evaluated if the memory associated with DZ withdrawal could be affected by changes in the contextual cues presented during withdrawal and by intrahippocampal administration of a PKM? inhibitor. We found that the context was relevant for the expression of withdrawal signs as changes in contextual cues prevented the expression of the anxiety-like behavior observed during plus-maze (PM) re-exposure, the associated enhanced synaptic plasticity and the increase in Arc expression. Furthermore, intrahippocampal administration of PKM? inhibitor previous to re-exposure to the PM test also impaired expression of anxiety-like behavior and the facilitated LTP. These results support the relevance of the hippocampal synaptic plasticity in the maintenance of the memory trace during benzodiazepines withdrawal, adding new evidences for common mechanisms between memory and drug addiction that can be intervened for treatment or prevention of this pathology.
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Genomic affinities of two 7,000-year-old Iberian hunter-gatherers.
Curr. Biol.
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The genetic background of the European Mesolithic and the extent of population replacement during the Neolithic is poorly understood, both due to the scarcity of human remains from that period and the inherent methodological difficulties of ancient DNA research. However, advances in sequencing technologies are both increasing data yields and providing supporting evidence for data authenticity, such as nucleotide misincorporation patterns. We use these methods to characterize both the mitochondrial DNA genome and generate shotgun genomic data from two exceptionally well-preserved 7,000-year-old Mesolithic individuals from La Braña-Arintero site in León (Northwestern Spain). The mitochondria of both individuals are assigned to U5b2c1, a haplotype common among the small number of other previously studied Mesolithic individuals from Northern and Central Europe. This suggests a remarkable genetic uniformity and little phylogeographic structure over a large geographic area of the pre-Neolithic populations. Using Approximate Bayesian Computation, a model of genetic continuity from Mesolithic to Neolithic populations is poorly supported. Furthermore, analyses of 1.34% and 0.53% of their nuclear genomes, containing about 50,000 and 20,000 ancestry informative SNPs, respectively, show that these two Mesolithic individuals are not related to current populations from either the Iberian Peninsula or Southern Europe.
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Segregation of regulatory polymorphisms with effects on the gluteus medius transcriptome in a purebred pig population.
PLoS ONE
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The main goal of the present study was to analyse the genetic architecture of mRNA expression in muscle, a tissue with an outmost economic importance for pig breeders. Previous studies have used F(2) crosses to detect porcine expression QTL (eQTL), so they contributed with data that mostly represents the between-breed component of eQTL variation. Herewith, we have analysed eQTL segregation in an outbred Duroc population using two groups of animals with divergent fatness profiles. This approach is particularly suitable to analyse the within-breed component of eQTL variation, with a special emphasis on loci involved in lipid metabolism.
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An ancestral miR-1304 allele present in Neanderthals regulates genes involved in enamel formation and could explain dental differences with modern humans.
Mol. Biol. Evol.
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Genetic changes in regulatory elements are likely to result in phenotypic effects that might explain population-specific as well as species-specific traits. MicroRNAs (miRNAs) are posttranscriptional repressors involved in the control of almost every biological process. These small noncoding RNAs are present in various phylogenetic groups, and a large number of them remain highly conserved at the sequence level. MicroRNA-mediated regulation depends on perfect matching between the seven nucleotides of its seed region and the target sequence usually located at the 3 untranslated region of the regulated gene. Hence, even single changes in seed regions are predicted to be deleterious as they may affect miRNA target specificity. In accordance to this, purifying selection has strongly acted on these regions. Comparison between the genomes of present-day humans from various populations, Neanderthal, and other nonhuman primates showed an miRNA, miR-1304, that carries a polymorphism on its seed region. The ancestral allele is found in Neanderthal, nonhuman primates, at low frequency (~5%) in modern Asian populations and rarely in Africans. Using miRNA target site prediction algorithms, we found that the derived allele increases the number of putative target genes for the derived miRNA more than ten-fold, indicating an important functional evolution for miR-1304. Analysis of the predicted targets for derived miR-1304 indicates an association with behavior and nervous system development and function. Two of the predicted target genes for the ancestral miR-1304 allele are important genes for teeth formation, enamelin, and amelotin. MicroRNA overexpression experiments using a luciferase-based assay showed that the ancestral version of miR-1304 reduces the enamelin- and amelotin-associated reporter gene expression by 50%, whereas the derived miR-1304 does not have any effect. Deletion of the corresponding target sites for miR-1304 in these dental genes avoided their repression, which further supports their regulation by the ancestral miR-1304. Morphological studies described several differences in the dentition of Neanderthals and present-day humans like slower dentition timing and thicker enamel for present-day humans. The observed miR-1304-mediated regulation of enamelin and amelotin could at least partially underlie these differences between the two Homo species as well as other still-unraveled phenotypic differences among modern human populations.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.